Our present invention pertains generally to the field of test equipment. More particularly, the invention relates to a decoder/analyzer test unit for enabling the rapid identification and isolation of failures or faults detected during various tests of a digital computer.
Large modern aircraft generally carry a flight guidance system which utilizes digital computers therein. The DC-10 aircraft, for example, employs a Bendix PB-100 Flight Guidance System that includes pitch, roll and yaw computers which have built in test equipment (BITE) for testing the computers. Each of the computers can be subjected by such built in test equipment to a sequence of discrete tests to determine if the computer under test is in good working order.
There are, however, a relatively large number of discrete tests that are performed in each of the different sequences of tests for the three computers and, when there is a failure in any of the discrete tests of a computer, the computer merely indicates a "no-go" condition thereof. An identification of the particular test or tests failed by the computer and the approximate or specific location of the fault therein are not provided by such computer. Thus, a faulty computer must be removed from its aircraft and long manhours are then required in further testing and troubleshooting of the computer.